tbuckley/cabot-search huggingface dataset:
Abstract 3974: Discovery and validation of therapeutic targets in immune cells by mass spectrometry-based proteomics
Authors: Yu-Wah Au, David Satijn, Martin Mehnert, Amaury Lachaud, Yuehan Feng, Jakob Vowinckel, Hélène Bon
Journal: Cancer Research (2023)

Abstract Immuno-oncology (IO) has substantially improved the survival of cancer patients over the past several years encouraging the discovery of novel IO targets which are typically proteins expressed on the surface of immune cells. Sensitive quantification of proteins in complex biological samples is routinely achieved by immunoassays that use antibodies specific to target proteins. Such approaches can be a limitation in IO drug discovery and development as de novo development of antibodies is associated with long lead times, high costs, and high failure rates. Protein quantification using mass spectrometry (MS) is agnostic to species and matrices and removes the barriers of availability or specificity of antibody-based assay. Further, MS proteomics workflows can support both large scale discovery studies but also represent an attractive alternative to targeted quantitative studies. The main purpose of this work is to assess the performance of the TrueDiscovery™ and TrueSignature™ MS-proteomics platforms for the deep proteome and surfaceome profiling of human primary and immortalized immune cells compared to flow cytometry solutions. We assess the number of quantified proteins and specifically the coverage of immune cell marker proteins in primary human immune cells across cell count groups from 2 million down to 2500 immune cells. In addition, we compared the quantification of a multiplexed surface antigens panel using TrueSignature™ and QIFI® flow cytometry platforms. We found that the applied MS-based proteomics workflows achieve high sensitivity and robustness in detection and quantification of immune cell markers down to 2500 primary immune cells. Additionally, we observed a strong correlation of the quantitative data derived from our MS-based proteomics workflows with flow cytometry supporting the substitution of immunoassays by MS-based proteomics workflows in target discovery and validation. Citation Format: Yu-Wah Au, David Satijn, Martin Mehnert, Amaury Lachaud, Yuehan Feng, Jakob Vowinckel, Hélène Bon. Discovery and validation of therapeutic targets in immune cells by mass spectrometry-based proteomics. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3974.
Abstract 4874: Hyperforin induces apoptosis and inhibits invasion via inhibiting AKT/NF-ΚB signaling pathway in colorectal cancer cells
Authors: Ying-Tzu Chen, I-Tsang Chiang, Yuan Chang, Fei-Ting Hsu
Journal: Cancer Research (2023)

Abstract Recently, the incidence of colorectal cancer (CRC) has been increasing year by year and has become the first incidence cancer in Taiwan. Epidermal growth factor receptor inhibitor (EGFR inhibitor) has been recognized as an important target of CRC. Therefore, targeting EGFR and its related signaling could be a potential strategy to overcome this disease. Hyperforin is a natural prenylated phloroglucinol and has been identified as the major molecule responsible for the antidepressant effects. Previous studies indicated that hyperforin has other potentially pharmacologically meaningful biological properties, including antibacterial ability and inhibition of inflammatory mediators. Numerous studies have also pointed out the anti-tumor potential of hyperforin is associated with the induction of apoptosis signaling. However, whether hyperforin may regulate CRC progression and its underlying mechanism is unclear. In our study, we used the MTT assay to prove the cytotoxicity of CRC cells (HT29 and HCT116 cells) was induced by hyperforin. We then used the flow cytometry to confirmed that hyperforin may induce both extrinsic/intrinsic apoptotic pathways in CRC cells. We further demonstrated hyperforin-induced apoptosis pathways is associated with mitochondrial-dependent apoptosis and death receptor dependent apoptosis. Then, transwell invasion, migration, and wound healing assay results proved the inhibition effect by hyperforin in HT29 and HCT116 cells. Additionally, we suggested that hyperforin can effectively inhibit EGFR downstream genes MEK-ERK and AKT signaling, as well as inhibit the phosphorylation of NF-ΚB and the nuclear translocation in CRC cells. In sum, our results show that hyperforin can inhibit the apoptosis and metastasis ability of CRC cells by inhibiting both AKT/NF- ΚB and ERK/NF-ΚB signaling pathway. Citation Format: Ying-Tzu Chen, I-Tsang Chiang, Yuan Chang, Fei-Ting Hsu. Hyperforin induces apoptosis and inhibits invasion via inhibiting AKT/NF-ΚB signaling pathway in colorectal cancer cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4874.
Abstract 2445: PPM1G enhances hepatocellular carcinoma stemness via interacting with YBX1
Authors: Shan Liu, Xiaona Fang, Jie Luo, Jiao Huang, Yuma Yang, Beilei Liu, Jinlin Huang, Ching Ngar Wong, Baifeng Zhang, Lanqi Gong, Liuxian Ban, Qian Yan, Xinyuan Guan
Journal: Cancer Research (2023)

Abstract PPM1G is a member of protein phosphatase family, marked as Mg2+/Mn2+ dependent 1G. PPM1G protein mainly has three domains: phosphatase domains at both ends and acidic domain (AD) in the middle. It was highly expressed in both embryonic stem cells and hepatocellular carcinoma (HCC) by mRNA-seq data. From pan-cancer view, it was up-regulated in tumor tissue of 24 pan-cancer types and predicted worse overall survival (OS) for 9 cancers. In GSE40267 dataset, PPM1G overexpressed significantly in lung metastasis HCC patients than patients without metastasis. And both from TCGA and ICGC-JP database analysis showed PPM1G was an independent poor prognostic factor for both OS and disease-free survival (DFS) in HCC patients. In vitro, our functional experiments showed that the stemness features such as sphere formation, ALDH assay and atRA (Tretinoin) assay were undermined by knock down (KD) of PPMIG. In HepG2 and 8024 KD cell lines, the tumor capacity of proliferation, cell-cycle, foci-formation, migration invasion and cisplatin induced apoptosis were also impaired. In vivo, KD of PPM1G strongly suppressed the subcutaneous and liver orthotopic tumor formation and lung metastasis and cancer stemness by limited dilution experiment was also significantly weakened. For the mechanism exploration, firstly, GO analysis showed genes highly positive correlated with PPM1G (Spearman R &amp;gt; 0.5) enriched in mRNA splicing. Secondly, YBX1 (role as RNA m5C and m6A reader protein and chemotherapy resistance gene) was screened out by three database (RBP2GO, HiPredict and GEPIA) followed with in vivo CO-IP experiment and immunofluorescence colocalization. The YBX1 expression level was not affected by PPM1G from Western Blot. Lastly, the AD of PPM1G but not the phosphatase domain was interacted with YBX1 by PPM1G cut-off and CO-IP experiments. So, the above evidence proved that PPM1G could interact with YBX1 to promote HCC stemness and tumor growth and metastasis. Citation Format: Shan Liu, Xiaona Fang, Jie Luo, Jiao Huang, Yuma Yang, Beilei Liu, Jinlin Huang, Ching Ngar Wong, Baifeng Zhang, Lanqi Gong, Liuxian Ban, Qian Yan, Xinyuan Guan. PPM1G enhances hepatocellular carcinoma stemness via interacting with YBX1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2445.
Abstract 3300: Development of a diagnostic antibody for anti-BTN1A1 therapy, a novel immune checkpoint inhibitor mutually exclusive of PD-L1/PD-1
Authors: Stephen S. Yoo
Journal: Cancer Research (2023)

Abstract Butyrophilin 1A1 (BTN1A1) is currently undergoing investigation in Phase 1 clinical trials as a novel immune checkpoint protein for the treatment of solid tumors. BTN1A1 exhibits a mutually exclusive expression pattern to that of PD-1/PD-L1, making anti-BTN1A1 antibody therapy an attractive option for cancer patients with PD-L1 refractory or relapsed disease. While current cancer immunotherapies have shown some efficacy against late-stage disease, there remains a major unmet medical need as a large number of patients fail to respond to current treatments. BTN1A1 has been studied at length in preclinical models to characterize its immunomodulatory functions, revealing its ability to inhibit the proliferation of activated T cells and the ability of these cells to kill tumor cells in vitro. In vivo, BTN1A1-overexpressing tumor models exhibit accelerated growth, whereas the growth of BTN1A1-deficient tumors is impaired in immunocompetent settings, supporting a role for this protein in the regulation of immune evasion. Here in, we present the development of a diagnostic antibody for use in the anti-BTN1A1 therapy clinical trials to enable the immunohistochemical (IHC) detection of human BTN1A1. A high-quality BTN1A1 antibody may help predict which patients are more likely to respond to BTN1A1 antibody-based cancer therapy, similar to the PD-L1 companion diagnostic test for anti-PD-L1/PD-1 therapy. The characterization of the developed BTN1A1 antibody was conducted via ELISA, Western blotting, confocal microscopy, and flow cytometry to demonstrate its overall performance. Validation was performed using formalin-fixed paraffin-embedded human tumor tissue samples to determine the analytical sensitivity and specificity of the IHC assay. This antibody was also found to be of value for imaging mass cytometry and flow cytometry experiments elucidating applicable clinical features of both human tumor tissues and immune cells. Specifically, the developed antibody can detect the robust expression of BTN1A1 on both cancer cells and immune cells, while also revealing the mutually exclusive expression of BTN1A1 and PD-L1. Finally, we demonstrate the capability of a BTN1A1 antibody that can be used to identify BTN1A1-positive patients with a high degree of analytical sensitivity and specificity. Citation Format: Stephen S. Yoo. Development of a diagnostic antibody for anti-BTN1A1 therapy, a novel immune checkpoint inhibitor mutually exclusive of PD-L1/PD-1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3300.
Abstract 1527: KY-CLC-mouse, a common light chain bi-specific antibody discovery platform
Authors: Hao Peng, Feng Hao, Guojin Wu, Feng He, Jinying Ning
Journal: Cancer Research (2023)

Abstract Bi-specific antibody (BsAb) is an attractive therapeutic antibody format for treating different diseases. The matching of light chains is the central issue of BsAb manufacturing. Here we developed a Common Light Chain mouse named KY-CLC-mouse. KY-CLC-mouse has no λ light chain expression with an identical κ light chain. This identical κ light chain was modified from a light chain that frequently appeared in mice and paired with different heavy chains. This light chain had good solubility and stability. It was also easy to humanize without post-translation modifications within CDRs. And the CDRs were modified to decrease immunogenicity. The mouse was validated by developing different monoclonal antibodies against various antigens with an identical light chain and high affinity. Mouse monoclonal antibodies against PD1, LAG-3, PD-L1, CD47, cMET, and EGFR were generated from the hybridoma of KY-CLC-mouse, with KD ranging from 0.1nM to 10nM. Humanized antibodies were derived from the above antibodies with high affinity. BsAb binding two of the above targets were generated by Knob-into-Hole (KiH) technology, such as fully humanized PD1xLAG-3 and CD47xPD-L1 BsAb. PD1xLAG-3 BsAb was simultaneously bound to PD1 and LAG-3 with a blockade of binding to their ligands, PD-L1 and MHCII. CD47xPD-L1 BsAb was simultaneously bound to CD47 and PD-L1 and inhibited their binding to ligands, SIPRα and PD1. Both BsAbs had typical mouse PK with a half-life longer than seven days. The above results indicated that KY-CLC-mouse is an efficient platform for discovering therapeutic antibodies with a common light chain. Citation Format: Hao Peng, Feng Hao, Guojin Wu, Feng He, Jinying Ning. KY-CLC-mouse, a common light chain bi-specific antibody discovery platform [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1527.
Abstract 3444: Role of AKR1C3 in converting reservoirs of DHEA-S into potent androgens that drive prostate cancer cell growth
Authors: Andrea J. Detlefsen, Ling Duan, Clementina Mesaros, Trevor M. Penning
Journal: Cancer Research (2023)

Abstract Castration resistant prostate cancer (CRPC) treatment aims to stop a resurgence of androgen receptor (AR) signaling with a class of therapeutics known as androgen receptor signaling inhibitors (ARSI). Through inhibition of CYP17A1, Abiraterone (Abi) prevents an upstream step in androgen biosynthesis, while Enzalutamide (ENZ) acts as an AR antagonist. Despite the early success of ARSI, a subset of patients develop resistance and succumb to the disease. One major mode of resistance is thought to occur when steroidogenic enzymes that are upregulated in CRPC convert weaker circulating precursors to testosterone (T) and dihydrotestosterone (DHT) to restore AR signaling. In this study, we identify a mechanism driving intratumoral steroidogenesis that involves AKR1C3 (type 5 17β-hydroxysteroid dehydrogenase type 5). AKR1C3 is a major steroidogenic enzyme in the prostate that is involved in all androgen biosynthetic pathways to T and DHT, upregulated in CRPC patients, and is a component of Abi and ENZ drug resistance. Previously with Taplin et al. we observed in patients on Leuprolide that T was reduced to 5 ng/dL, and the addition of Abi lowered DHEA-S by 90% (from 230,000 ng/dL to 22,000 ng/dL). However, the DHEA-S that remained was 4,000x greater than circulating T, making it a reservoir for intratumoral steroidogenesis post Abi treatment. Here, we demonstrate that post-Abi concentrations of DHEA-S, and castrate levels of DHEA-S (post-leuprolide but pre-Abi treatment), which also corresponds to DHEA-S levels patients on ENZ are 1) converted to T in an AKR1C3-dependent manner in prostate cancer (PCa) cells, and 2) sufficient to stimulate AKR1C3-dependent cell growth. Our observations are consistent across both primary and metastatic PCa cell lines, CWR22PC and DuCaP, respectively. Androgen measurements were made using our highly sensitive and specific stable isotope dilution liquid chromatography tandem mass spectrometry (SID-LC-MS/MS) method. Additionally, we demonstrate AKR1C3-dependence using genetic and pharmacological approaches with an AKR1C3 stable knockdown for each cell line and two AKR1C3 competitive inhibitors. Taken together, we have identified a mechanism of resistance to ARSIs common to both primary and metastatic cell lines that operates through AKR1C3’s intratumoral conversion of DHEA-S to potent androgens that drive prostate cancer growth. Citation Format: Andrea J. Detlefsen, Ling Duan, Clementina Mesaros, Trevor M. Penning. Role of AKR1C3 in converting reservoirs of DHEA-S into potent androgens that drive prostate cancer cell growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3444.
Abstract 4494: Multi-specific cMet x EGFR x VEGF antibody for difficult to treat cancers
Authors: Mark Chiu
Journal: Cancer Research (2023)

Abstract Cancers such as TNBC, pancreatic, and gastric are difficult to treat due to diverse etiologies. Several subtypes of these cancers are driven by abnormal EGFR signaling, increased cMET activation, and VEGF linked angiogenesis which are responsible for tumor growth and metastasis. TAVO412, a humanized multi-specific antibody with two distinct anti-EGFR nanobody domains, an anti-cMet Fab arm, and an anti-VEGF ScFv domain, was designed to treat patients with these unmet medical needs. In addition, the Fc domain allows for the heterodimerization, antibody-like pharmacokinetic profile, and additional mutations that enhance the Fc effector functional activity. In preclinical xenograft models, TAVO412 demonstrated strong tumor growth inhibition effects on TNBC, PDAC, GC or NSCLC cell line-derived tumors. The mechanisms of action included selective and potent binding to EGFR, cMet, and VEGF at lower pH values found in the solid tumor environment; effective blocking of EGFR and cMet pathways that drove cancer cell growth and proliferation; shutdown of VEGF mediated angiogenesis; and potent and efficacious Fc effector function that enhanced ADCC, ADCP, and CDC. TAVO412 had better TGI than analogous molecules. TAVO412 also demonstrated strong tumor growth inhibition against NSCLC patient derived xenograft (PDX) models with mutant EGFR and cMet genotypes. Each of the binding arms had cross reactivity with the cynomolgus monkey orthologues allowing the cyno model to be a relevant toxicology model. In the pivotal GLP toxicology study in cynomolgus monkeys, TAVO412 was well tolerated, had no major organ toxicities, observations were mostly consistent with EGFR-related effects and recoverable. In conclusion, TAVO412 was successfully discovered and developed for hard-to-treat solid tumors. This drug is expected to be safe and efficacious in cancer patients. The IND application was approved by the US FDA in October 2022. A first-in-human, 2-Part Phase 1 study to examine the preliminary efficacy, safety, tolerability, pharmacokinetic/pharmacodynamic parameters; maximum tolerated dose/recommended phase 2 dose of TAVO412 will be starting in the first quarter of 2023. Citation Format: Mark Chiu. Multi-specific cMet x EGFR x VEGF antibody for difficult to treat cancers. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4494.
Abstract 3641: Loss of Smad4 induces SPP1 secretion and immunosuppressive myeloid cell formation in pancreatic ductal adenocarcinoma
Authors: Gilbert Z. Murimwa, Francesca Rossi, Henry K. Fleming, Zeynep Yazgan, Dina Alzhanova, Huocong Huang, Rolf A. Brekken
Journal: Cancer Research (2023)

Abstract Up to 50% of pancreatic ductal adenocarcinomas (PDA) harbor mutations in canonical TGFß pathway genes such as SMAD4 and TGFBR2. SMAD4 mutations have been shown to drive resistance to chemotherapy, metastasis, and margin positivity following surgical resection. To characterize the unique tumor microenvironment of SMAD4 mutant PDA, we developed isogenic, orthotopic mouse models using CRISPR mediated knockout of Smad4 in a cell line derived from KPfC (KrasLSL-G12D;Trp53fl/fl;Pdx1Cre) mice, a genetically engineered mouse model of pancreatic cancer. To characterize the alteration of the secretome caused by the loss of Smad4, we performed proteomic analysis with conditioned media collected from Smad4 wildtype and mutant cancer cell clones. Interestingly, the loss of Smad4 resulted in the production of neuroendocrine related factors. In addition, gene ontology analysis with the secretome suggested that these factors were associated with neuronal processes. These data indicate that loss of Smad4 in PDA cancer cells may lead to a neuroendocrine signature change. In particular, we found one of the most up-regulated secreted factors in the mutant cells was SPP1, which has been shown to promote tumor progression by affecting cancer cell stemness and macrophage polarization. To validate the proteomic results, we established orthotopic models with Smad4 wildtype and mutant clones. We found that loss of Smad4 resulted in larger tumor growth. Moreover, immunohistochemistry showed a significant up-regulation of SPP1 in the cancer cells of Smad4 mutant tumors. To further profile the alteration of immune landscape, we stained for markers of myeloid cells and lymphocytes. We found that Smad4 mutant tumors had an immunosuppressive microenvironment characterized by increased M2 macrophage, neutrophil and MDSC infiltration. Altogether, our study suggests that loss of SMAD4 in PDA may induce a neuroendocrine signature with increased SPP1 secretion in cancer cells. The production of this unique cancer cell secretome may result in a microenvironment marked by immunosuppressive myeloid cells. Citation Format: Gilbert Z. Murimwa, Francesca Rossi, Henry K. Fleming, Zeynep Yazgan, Dina Alzhanova, Huocong Huang, Rolf A. Brekken. Loss of Smad4 induces SPP1 secretion and immunosuppressive myeloid cell formation in pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3641.
Abstract 1593: Synergistic effect of SH003 and Docetaxel by targeting a metabolic pathway in non-small cell lung cancer cells
Authors: Yu-Jeong Choi, Kangwook Lee, Sooyeon Kang, Seo Yeon Lee, Hyun-Ha Hwang, Seong-Gyu Ko
Journal: Cancer Research (2023)

Abstract The identification of molecular biomarkers that can predict the response of cancer treatment facilitates more clear targeted therapy by lowering the side effect. Therefore, the present study investigated the key regulatory genes that determine the efficacy of SH003, a herbal medicine, combined with docetaxel (DTX) in non-small cell lung cancer cells. We identified that the combination treatment inhibited the process of the de novo biosynthesis of pyrimidine nucleotide via the reduction of the related enzyme expressions, resulting in DNA damage and apoptosis. However, we found that NSCLC cells have different sensitivities to combination treatment. As a result, the difference in sensitivity was determined by the p53 gene expression pattern of lung cancer cells, indicating that the treatment response of combination enhances by activating p53 in p53 wild-type lung cancer. Lung cancer cells harboring p53 mutations were resistant to the metabolic inhibition by the combination, whereas this effect was restored when p53 is expressed normally. In conclusion, this study revealed the genetic characteristics of cancer cells that are susceptible to treatment response when SH003 and DTX are combined, suggesting that p53 will be an important predictor of combination treatment. Citation Format: Yu-Jeong Choi, Kangwook Lee, Sooyeon Kang, Seo Yeon Lee, Hyun-Ha Hwang, Seong-Gyu Ko. Synergistic effect of SH003 and Docetaxel by targeting a metabolic pathway in non-small cell lung cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1593.